Sandra Mendoza and Marco Zavaleta 8 th period. Our section was about the vocabulary that we have learned from the section. We had to fill in the blanks.

VOCABULARY PG. # 227

Sandra Mendoza and

Marco Zavaleta 8th period

Summarize:

Our section was about the vocabulary that we have learned from the section. We had to fill in the blanks in the sentence that described the words.

Things you should remember:

You should remember what the words mean and the way they are used in proofs to be the reason for a statement.

Answers:

1. H2. G3. D4. J5. A6. C7. B8. F

By: Elizabeth & Steven

4-1

Triangles can be identified by their angles, obtuse or right. Also by their sides as scalene, isosceles, or equilateral.

Summary

Acute triangle= less then 90 degrees obtuse triangle= more then 90 degreesright triangle= is 90 degreesscalene triangle= all different sidesisosceles triangle=two same sidesequilateral triangle= all same sides

Remember

1. obtuse, isosceles triangle 2. Right angle, right triangle3. equiangular, equilateral triangle

Problem Solving

ANGLES O

F

TRIANGLE

S

4-2

Made by :Cruz GonzalezLesly Hernandez

Summary

The sum of measures of the angles of a triangle is 180.

The measure of an exterior angle is equal to the sum of the measures of the two re mote interior angles.

REMEMBER!

Angle sum theorem – the sum of the measures of the angles of a triangle is 180

All 3 angles from a triangle when added up are equal to 180

Answers To Problems (:

12. 85 13. 25 14. 95

CONGRUENT TRIANGLES

4-3By: Natalie Martinez

Mildred ZamoraEdgar Peralta

Congruent Triangles Triangles that are the same size and

shape are congruent triangles. Each triangle has three angles and three

sides. If all six of the corresponding parts of two

triangles are congruent, then the triangles are congruent.

Congruent Triangles• If ABC is congruent to EFG, the vertices

of the two triangles correspond in the same order as the letters naming the triangles

• This correspondence of vertices can be used to name the corresponding congruent sides and angles of the two triangles

• The corresponding sides and angles can be determined from any congruence statement by following the order of the letters.

EXAMPLE: If EFG = JKL, name the corresponding congruent angles and sides

E J, F K, G L, EF JK, FG KL, and EG JL

REMEMBER: All line segments should have a line above the two letters!!!!!!!!

15.) EFG DCB- E D, F C, G B, EF DC, FG CB, EG DB16.) LCD GCF- L G, C C, D F, LC GC, CD CF, LD GF17.) NCK KER- N K, C E , K R, NC KE, CK ER, NK KR

4-4 PROVING CONGRUENCE

Angela, Jessica, Javier

Proving Congruence

This sections explains how you can determine whether two triangles are congruent.

What you need to know

To determine if two triangles are congruent you need to use the distance formula.

Each point of a triangle must be known. Determine if the corresponding side of

one triangle is congruent to the corresponding side of another triangle.

Problem

Determine whether MNP is congruent to

QRS. M(0,3) N(-4,3) P(-4,6) Q(5,6) R(2,6) S(2,2) N R

M P Q S

Answer Use the distance formula to identify if the

corresponding sides are congruent. REMEMBER: Take the square root of your final answer!!!!

MN= (3-7) ² + (2-4) ² QR= (-2-(-4) ) ² + (3-7) ² -4²+ 2² = 20 2²+ 4² = 20NP= (7-6) ² + (4-6) ² RS= (-4(-6) ) ² + (7-6) ²1²+2²= 5 2²+1²= 5MP= (3-6) ² + (2-6) ² QS= (2-(-6) ) ² + (3 – 6) ²-3²+ 4²= 25 4²+3²=25All corresponding sides are congruent, SSS, triangle MNP is congruent to triangle QRS.

SECTION 4-5

Proving Congruence – ASA, AAS

Angle-Side-Angle

Angle-Side-Side

Num

ber

21.

Statements Reasons

1. ∆DGC is congruent to ∆DGE

1. Given

2. ∆GCF is congruent to ∆GEF

2. Given

Angle

-Sid

e-

Angle

(AS

A)

If two pairs of corresponding angles

and the included side

of two triangles are congruent, then the triangles are congruent.

Angle

-Angle

-Sid

e(A

AS)

If two pairs of corresponding angles

and the pair of corresponding non-included sides of two

triangles are congruent, then the triangles are congruent.

ISOSCELES TRIANGLES

Section 4-6

Things to know

Properties of isosceles triangles Two sides of a triangle are congruent if

and only if the angles opposite those sides are congruent

A triangle is equilateral if and only if it is equiangular

Answers

22) Measure of angle PUQ = 3223) Measure of angle R = 4024) Measure of angle R = 3025) Measure of angle P =80